I inherited a Kenmore 80 Series gas dryer from the previous owners of my house. If I put it on a timed dry cycle for 80 minutes, it usually stops before the 80 minutes are up. Sometimes, when I press the start button, it refuses altogether to stop, just buzzing while the button is depressed. When it runs, it sounds to me like it's making a disturbing scraping sound, though I'm not sure if that's normal or a recent development.
I took out the drum and tried turning the motor by hand. It turns, and makes a squeaking sound as it turns.
What could be causing these symptoms?
Does replacing the motor seem like a worthwhile step?
What other diagnostics should I do?